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% SAT_Const: Definition of astronomical and mathematical constants
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% Last modified:   2019/11/03   Meysam Mahooti
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% Mathematical constants
const.pi2       = 2*pi;                % 2pi
const.Rad       = pi/180;              % Radians per degree
const.Deg       = 180/pi;              % Degrees per radian
const.Arcs      = 3600*180/pi;         % Arcseconds per radian

% General
const.MJD_J2000 = 51544.5;             % Modified Julian Date of J2000
const.T_B1950   = -0.500002108;        % Epoch B1950
const.c_light   = 299792457.999999984; % Speed of light  [m/s]; DE436
const.AU        = 149597870699.999988; % Astronomical unit [m]; DE436

% Physical parameters of the Earth, Sun and Moon

% Equatorial radius and flattening
const.R_Earth   = 6378.1363e3;         % Earth's radius [m]; DE436
const.f_Earth   = 1/298.257223563;     % Flattening; WGS-84
const.R_Sun     = 696000e3;            % Sun's radius [m]; DE436
const.R_Moon    = 1738e3;              % Moon's radius [m]; DE436

% Earth rotation (derivative of GMST at J2000; differs from inertial period by precession)
const.omega_Earth = 15.04106717866910/3600*const.Rad; % [rad/s]; WGS-84

% Gravitational coefficients
const.GM_Earth   = 398600.4418e9;         			   % [m^3/s^2]; WGS-84
const.GM_Sun     = 132712440041.9394e9; 			   % [m^3/s^2]; DE436
const.GM_Moon    = const.GM_Earth/81.3005682168675747; % [m^3/s^2]; DE436
const.GM_Mercury = 22031.78000000002e9; 		       % [m^3/s^2]; DE436
const.GM_Venus   = 324858.5920000001e9; 		       % [m^3/s^2]; DE436
const.GM_Mars    = 42828.37521400003e9;	  			   % [m^3/s^2]; DE436
const.GM_Jupiter = 126712764.1334462e9;    			   % [m^3/s^2]; DE436
const.GM_Saturn  = 37940585.20000001e9;   			   % [m^3/s^2]; DE436
const.GM_Uranus  = 5794556.465751793e9;    			   % [m^3/s^2]; DE436
const.GM_Neptune = 6836527.100580024e9;    			   % [m^3/s^2]; DE436
const.GM_Pluto   = 975.5011758767654e9;	  			   % [m^3/s^2]; DE436
                   

% Solar radiation pressure at 1 AU
const.P_Sol = 1367/const.c_light; % [N/m^2] (1367 W/m^2); IERS

